An XSB (XSokoban) file is a text file defining one or more levels; any XSB file can be used with CPSokoban by choosing File->Open level set. A level is described using the seven characters in the table below. Multiple levels are separated by blank lines and/or text. To CPSokoban, a line in which every character is one of the seven below, and at least one is not a space, is assumed to describe one row of a level. Any line not of that form is assumed to be a separator, and is otherwise ignored.
| Character | Interpretation |
|---|---|
| <space> | Empty square |
| . | Goal square |
| # | Wall |
| $ | Stone on an empty square |
| * | Stone on a goal square |
| @ | Robot on an empty square |
| + | Robot on a goal square |